Pipe sleeve



C. O. TOLF, JR

Oct. 10, 1967 PIPE SLEEVE 2 Sheets-Sheet 1 INVENTOR.

CQT To BY MM Filed July l5. 1964 Ocf. 10, 1967 c. o. ToLF, JR

PIPE SLEEVE 2 Sheets-Sheet 2 Filed July l5. 1964 'l'. 2

United States Patent C) 3,346,230 PIPE SLEEVE Carl 0. Tolf, Jr., Park Ridge, Ill., assignor, by mesne assignments, to Construction Accessories Mfg. Corp., Rosemont, Ill.

Filed July 15, 1964, Ser. No. 382,719 v 4 Claims. (Cl. 249-177) This invention relates to improvements in hole forming devices of the type used when pouring concrete slabs or the like.

In the construction industry, it has long been the practice to use hole forming devices of one sort or another when pouring concrete slabs such as floors, walls, roofs, or the like. Thus, the finished slab is provided with preformed holes at desired locations so as to accommodate the subsequent installation of plumbing lines, electrical conduits, or the like without the necessity of drilling holes through the concrete. Such devices are com monly known as pipe sleeves but have also been referred to as cores, hole liners, and wall or floor sleeves.

Heretofore, pipe sleeves have most often been fabricated, or partially fabricated, at the job site by forming open ended cylinders from sheet metal. Tabs are bent outwardly at one end of the cylinder for afxing the sleeve to one of the temporary forms against which the slab is poured. After the sleeve has been attached to the form, usually by nails, it is filled with sand, wadded burlap, crumpled paper or the lie in order to prevent concrete from entering the sleeve during the pouring and finishing operations. In some instances removable end caps have been provided for closing the outer end of the pipe sleeve. It has also been proposed heretofore to use pipe sleeves formed from two telescopically intertting metal cylinder sections so as to permit adjustment of the sleeve for accommodating different slab thicknesses.

It is a primary object of the present invention to provide a novel and improved pipe sleeve construction having numerous advantages over the pipe sleeves previously known.

A more specific object of the invention is to provide a novel and improved pipe sleeve made of deectable plastic material, par-ticularly polyethylene.

Another object of the invention is to provide an improved pipe sleeve having a novel telescopic adjustment feature.

A further object of the invention is to provide a novel and improved unitary pipe sleeve which can be used as such but which is especially adapted to be separated into two telescopically collapsible sections for adjusting the length of the sleeve.

An additional object of the invention is to provide a novel and improved pipe sleeve having special provisions such that two sleeve units can be fitted together to provide an extended pipe sleeve or can be nested compactly for storage and shipment.

Still another object of the invention is to provide a novel and improved pipe sleeve of the aforementioned character which is also inexpensive, light weight, rustproof and weatherproof, and is readily reusable if desired.

Other objects and advantages of the invention will be apparent from the subsequent detailed description taken in conjunction with the accompanying drawing, wherein:

FIG. l is a small scale perspective view of `a pipe sleeve comprising one specific embodiment of the invention, the sleeve being shown in place in a concrete slab;

FIG. 2 is an enlarged scale vertical sectional view of the pipe sleeve per se;

FIG. 3 is a transverse sectional view taken along the line 3 3 of FIG. 2;

ICC

FIG. 4 is a fragmentary vertical sectional view on a further enlarged scale, as taken along the line 4-4 of FIG. 3;

FIG. 5 is a fragmentary vertical sectional view showing the manner in which two pipe sleeves may be telescopically interfitted to provide a sleeve of extended length;

FIG. 6 is a reduced scale fragmentary transverse sectional view taken along the line 6 6 of FIG. 5;

FIG. 7 is a view similar to FIG. 5 but showing the manner in which the two sleeves may be -compactly nested for shipping or storage purposes;

FIG. 8 is a fragmentary vertical sectional view showing one position of telescopic adjustment of the separated upper and lower sections of the pipe sleeve;

FIG. 9 is a view similar to FIG. 8 but showing another position of telescopic adjustment; and

FIG. l0 is a fragmentary transverse sectional view taken along the line I0-I0 of FIG. 9.

The pipe sleeve of the present invention is designated generally at 2li in FIG. 1 and comprises a unitary cylindrical member 21 having an integral wall or closure 22 at one end and a radially extending circumferential flange 23 at the other end. The flange 23 has perforations 24 so that the sleeve `can be aflxed to a temporary form, such as a wood panel 26, by means of nails 27. The ange 23 is marked at 90 intervals with locating indicia, such as the arrows 25 (FIG. 3), to assist the user in accurately positioning the sleeve at a predetermined location on the form 26. A concrete slab 28 has been poured on the form 26 and surrounds the sleeve 20. After the concrete has hardened, the form 26 is removed and the attached sleeve 2li will usually be withdrawn with the form to leave a suitable hole 29 in the slab 2S. Although not evident from the drawing, the sleeve 2i) preferably has a slight overall narrowing taper from bottom to top to assist in withdrawal from the concrete slab. However, if the sleeve 20 happens to stick in the concrete and is not removed with the form or if for any reason it is desired to leave the sleeve 20 in place in the slab 28, then the end wall 22 must be removed as hereinafter described.

In FIGS. 2-4 the structural details of the sleeve 20 are shown. Preferably, the sleeve 20 is made from a high strength deflectable plastic material such as polyethylene or polypropylene. High density linear polyethylene is a particularly useful material from which the pipe sleeve can be readily formed by injection molding. The sleeve can be manufactured in varying diameters to provide different size holes, such as two inches, four inches, six inches, etc. The sleeve 20 herein illustrated is a typical large diameter sleeve as required for an eight inch hole. For any given diameter, the sleeve is manufactured in a xed length but it is a particular advantage of the invention that the length of a sleeve is capable of being adjusted in the field in a rapid and simple manner.

Thus, the cylindrical body portion 21 of the pipe sleeve 21B has a lower section 31, which is provided with the aperture-d flange 23, and an axially aligned upper section 32 having the integral end closure 22. As will be evident rom FIGS. 2 and 4, the upper cylindrical sleeve section 32 has an external diameter which is slightly smaller than the internal diameter of the lower cylindrical sleeve section 31 for a purpose to be described. The adjacent ends of the sleeve sections 31 and 32 are integrally connected by means of an annular web portion 33 of reduced thickness, and the outer wall surface portion of the cylindrical section 3l preferably extends upwardly so as to yform with the web portion 33 and the adjacent outer wall of the sleeve section 32 a shoulder or ledge having a shallow annular groove or recess 34 which extends circum- -ferentially entirely around the sleeve. The purpose of the groove 34 is also explained below.

An annular section 36 of reduced thickness is provided around the end wall 22 at the juncture thereof with the sleeve section 32. The end wall 22 is also provided with a plurality of small slots 37 (FIGS. l and 4) which Vdo not interfere with the normal closure function but are of sufficient size to permit the insertion of a knife blade or other cutting tool. Consequently, if it is necessary to remove the end wall 22, as when the pipe sleeve remains in the concrete slab, such removal can sometimes be accomplished by means of a sharp blow with a hammer or other tool against the wall 22 so as to effect tearing or failure of the weakened wall section 36. In other instances, removal of the end wall 22 is more readily effected by cutting through the thin section 36 with a knife, the slots 37 providing convenient points of entry for the knife blade.

The sleeve section 31 is provided at its lower end adjacent the ange 23 with three internal pads or ribs 38 which are located at equal circumferential spacings around the interior of the sleeve. Each pad 38 has a transverse groove 39. The upper end portion of the upper sleeve section 32 has three equally spaced external beads or projections 41 which are spaced below the end wall 22. As will be evident from FIG. 2, the circumferential spacing between the beads 41 is such that the spaced pads 38 are interposed in the spaces between the beads 41 though at the opposite end of the pipe sleeve unit.

As shown in FIGS. 5 and 6, a pair of pipe sleeve units 20 and 20 can be interconnected by insertion of the smaller diameter upper end portion 32 of the unit 2@ into the large diameter lower end portion 31 of the unit 20 withy the grooved pads 3S of the unit 2d in axial alignment with the beads 41 of the unit 2t). The dimensions of the grooves 39 and the beads 41 are such that by pressing the sleeve units together the beads 41 are deflected and then snap into the grooves 39 to provide a snug interlocking relationship suicient to retain the pair of pipe sleeves together as a unit. Thus, an extra long pipe sleeve is provided for use with unusually thick concrete slabs. For example, if each pipe sleeve unit 2d and 20 is eight inches long, as previously mentioned, the grooves 39 may conveniently be located one-half inch above the lower ends of the sleeve units and the beads 41 may be located one and one-half inches below the upper ends of the sleeve units so that the pair of interconnected sleeve units 20-20 has an overall length of fourteen inches. Obviously, any desired number of pipe sleeve units can be connected together in the manner Shown. Also, it will be understood that only the lower sleeve unit 20, which is attached to the form 26 by the ange 23, can be withdrawn upon removal of the form. The iiange 23 will become embedded in the concrete slab thus preventing withdrawal of the sleeve 21) and necessitating removal of the end wall 22 in the manner described above.

FIG. 7 illustrates the manner in which the two pipe sleeve units 2d' and 20 can be pressed together to a further extent than in FIG. 5. For this purpose, the sleeve units are interfitted'with the pads 38 of the sleeve 20 in axial alignment with the spaces between the beads 41 of the sleeve 2t). Consequently, there is no interengagement of the beads 41 with the grooves 39 and the two sleeves can be telescoped to the maximum extent until the lower anged end of the sleeve 21B', and particularly the inwardly projecting pads 38 thereof, seats against the ledge or shoulder having the groove 34 at the upper end of the sleeve section 31. Thus, the two pipe sleeve units 2d and 20* are c-ompactly nested or stacked for shipment and storage purposes but can readily be separated when desired. It will be understood that any desired number of pipe sleeve units can be nested or stacked together in the manner shown in FIG. 7.

Although FIGS. 5-6 show the pipe sleeve units 2t) and Ztl in one interlocked position and FIG. 7 shows the units in a different nested position, it should also be understood that the invention contemplates adjusting the two units to any intermediate position therebetween. For this purpose, the three pads 38 of the upper unit 20 provide a sufficiently tight frictional fit with the outer surface of the upper sleeve section 32 of the unit 2t) to retain the two units in any desired adjusted position. To facilitate such adjustment, the exterior of each pipe sleeve unit is preferably marked with graduations 42 (FIG. l), for example at one inch intervals, so as to obtain a desired total sleeve length as quickly and easily as possible.

In the event that it becomes necessary to use the pipe sleeve 2i) in connection with a concrete slab having a thickness less than the length of the sleeve Ztl, the invention makes provision for collapsing a single pipe sleeve to obtain a shorter length sleeve. By cutting through or otherwise disrupting the thin connecting web 33, the upper and lower sleeve sections 32 and 31 can be completely severed or detached so as to permit the smaller diameter upper section 32 to be telescoped to any desired degree inside the larger diameter lower section 31, as seen in FIGS. 8-10. The grooved external shoulder or ledge 34 between the sleeve sections 31 and 32 provides a convenient depressed guide channel for the tip of a knife blade or other tool, thereby facilitating and simplifying the cutting operation.

For regulating the telescopic fit between the severed sleeve sections 31 and 32, a plurality of projections or protuberances are provided on one of the concentric sleeve sections for frictionally engaging the opposed wall surface of the other sleeve section. In the illustrated embodiment of the invention, these projections are in the form of three sets of small integral tabs 43, 44, and 45 of generally triangular cross vsection which extend inwardly from the inner wall of the lower sleeve section 31 at predetermined locations. Each set consists of three tabs spaced at equal circumferential distances around the interior of the sleeve section 31 at a given elevation, and the respective sets of tabs are preferably spaced at equal distances axially of the sleeve section 31. Thus, if the sleeve section 31 is four inches in length as previously mentioned, the tabs 43, 44, and 45 are located one inch, two inches, and three inches, respectively, below the upper end of the sleeve section 31, as best seen in FIGS. 2 and 4. Moreover, as will be evident from FIGS. 2, 3 and 4, the orientation of the respective sets of tabs 43', 44, and 45is such that the nine tabs are spaced 40 apart circumferentially of the sleeve section 31 and no two tabs are superimposed above each other axially of the sleeve. Thus, the tabs are distributed substantially uniformly around the inner surface of the sleeve section 31 for frictionally engaging the adjacent exterior surface of the telescoping sleeve section 32. By use of the graduation markings 42 on the sleeve section 32 the two sleeve sections can be telescoped to the desired degree and are retained in the selected position by the frictional resistance of the tabs 43, 44, or 45.

The tabs 43, 44, and 45 may also serve the additional function of stop members to provide more or less definite telescoped positions of the sleeve sections 31 and 32 even though any desired intermediate position can also be selected. For example, as shown in FIG. 8, if the tabs 43 are located one inch below the upper end of the sleeve section 31, the upper sleeve section 32 can be telescoped until the lower end thereof engages the projecting tabs 43 and cornes to a definite stop about one inch inside the sleeve section 32, thereby providing a combined sleeve length of seven inches instead of the originaleight inch length. The angularly extending portion of the severed web 33 at the lower end of the sleeve section 32 frictionally engages the interior of the sleeve section 31 to a sufficient extent to retain the sleeve sections in adjusted position.

The tabs V43, 44, and 45 are short and stubby and, therefore, relatively rigid so as to impose a certain degree of resistance to further telescoping movement of the sleeve section 32 beyond the position shown in FIG. 8. However, by sumcient telescoping pressure, the tabs 43 cause the wall of the sleeve section 32 to be deiiected inwardly at the locations of the tabs 43, as shown in slightly exaggerated form in FIG. 9, so that the sleeve section 32 can be pushed past the tabs 43V until the lower end thereof engages the tabs 44 and comes to a second definite stop position. Assuming that the tabs 44 are two inches from the ends of the sleeve section 32, a combined sleeve length of six inches is thereby obtained. The inward local deflection of the sleeve section 32 due to the action of the tabs 43 also causes the sleeve wall to bulge outwardly to a slight extent in the regions between the tabs 43, and consequently the outwardly bulged wall portions are shifted into more positive overlaying engagement with the tabs 44. In similar fashion, the sleeve section 32 can be pressed further into the sleeve section 31 past the tabs 44 until another stop position (not shown) is reached when the end of the sleeve section 32 engages the tabs 45. The tabs 44 cause similar local deflection of the sleeve wall with similar bulging in the areas overlying the tabs 45. Consequently, the advantage of circumferentially offsetting the respective tabs `43, 44, 45 so that no two tabs are aligned axially of the sleeve will be readily apparent.

Although the stop function of the tabs 43, 44, and 45 as just described is advantageous in that it makes it possible to obtain rapid adjustment of the telescoping sleeve sections in predetermined increments, it should be understood that such stop function is not an indispensable feature of the invention. The primary funtion of the tabs is to provide desired frictional resistance between the telescoping sleeve sections so as to retain the sleeve sections in any desired intermediate position of adjustment.

From the fore-going description, it will be recognized that the pipe sleeve of the present invention provides a highly advantageous combination of features not previously available in the art.

The use of polyethylene plastic or the like makes it possible to provide a completely preformed pipe sleeve requiring no fabrication steps in the field. At the same time the sleeve can be inexpensively manufactured by conventional injection molding techniques; it is light weight for minimum shipping cost; it has good impact strength so as to be virtually indestructable under normal usage; and it is fully rustproof and weatherproof.

The pipe sleeve has an integrally formed cap or cover which eliminates the use of sand or other fillers and avoids the necessity of a separate cover member which can easily be lost and requires an additional field operation. At the same time the integral cover can be removed easily whenever required.

In most instances the sleeve can be removed from the con-crete and reused if desired. Such removal is facilitated by the slight'overall taper between the opposite ends of the sleeve and also by the well-known nonadherent surface characteristic of polyethylene which renders the sleeve readily releasable from the hardened concrete.

As described in connection with FIG. 7, the sleeves are self-stacking in compact relation for shipping and storage purposes. As shown in FIGS. 5-6, the sleeves are easily interconnected in those instances where an extra length sleeve is needed. Finally, as shown in FIGS. 8-10, each sleeve unit can be telescoped in a unique manner so as to fit any particular slab thickness while at the same time retaining the integral cover protection and obtaining a flush surface relationship with the slab to avoid interference with trowelling or other finishing operations.

Although not illustrated in the drawings, those skilled in the art will recognize that the herein described pipe sleeve is readily adapted for use as a wall sleeve between a pair of spaced vertical wall forms. In such case, a sleeve unit 20 is severed at the web portion 33 and the detached sleeve section 31 with the attached flange portion 23 is then telescoped over the closed end of a second pipe sleeve unit so that the flange portions are disposed at opposite ends of the combined parts.

Although the invention has been described with particular reference to the illustrated embodiment thereof, it should be understood that alternative and equivalent structures may be resorted to without departing from the scope of the invention as defined in the appended claims.

I claim:

1. A pipe sleeve comprising a one-piece tubular member of deliectable plastic material having a pair of axially aligned cylindrical sections one of which has a slightly larger diameter than the other, attaching means at the outermost end of said one section, closure means at the outermost end of said other section, said sections having an external shoulder therebetween, means defining a plurality of circumferentially spaced pads at the interior of said one section adjacent said outermost end thereof, said pads having recesses therein, and a plurality of circumferentially spaced projections at the exterior of said other section adjacent said outermost end thereof, said projections being complementary to said recesses, whereby a pair of said sleeves can be fitted together endwise with the pads of one sleeve frictionally engaging the exterior surface of the smaller diameter section of the other sleeve for frictionally retaining the sleeves in desired adjusted position, the recesses of the pads on said one sleeve and the projections on said other sleeve being engageable when the same are axially aligned for interlocking the sleeves in one adjusted position, and the sleeves being movable to a more compact nested position with the pads of said one sleeve abutting the shoulder of said other sleeve when the pads on said one sleeve are axially aligned with the spaces between the projections on the other sleeve.

2. A pipe sleeve comprising a one-piece tubular member of deflectable plastic material having a pair of axially aligned cylindrical sections one of which has a slightly larger diameter than the other, connecting means normally interconnecting the innermost ends of said sections to provide a unitary sleeve, said connecting means being disruptible for disconnecting said sections whereby said other section can be telescoped within said one section for adjusting the length of the pipe sleeve, attaching means at the outermost end of said one section for securing the pipe sleeve to a form, end closure means at the outermost end of said other section, said one section being provided with a plurality of integral protuberances extending inwardly from the inner surface of said one section and adapted to frictionally engage the exterior of said other section when the latter is telescoped within said one section, said protuberances being disposed at a plurality of axially spaced locations along the length of said one section for initial stopping engagement with the innermost end of said other section and said other section being locally deectable inwardly to permit the innermost end thereof to be telescoped forcibly beyond the protuberances at a `given axial location, whereby said protuberances function as stops for axially positioning said other section at predetermined axial increments but also permitting intermediate positions of adjustment, a plurality of circumferentially spaced inwardly projecting pads at the interior of said one section adjacent said outermost end thereof, said pads having recesses therein, and a plurality of circumferentially spaced projections at the exterior of said other section adjacent said outermost end thereof, said projections being complementary to said recesses, whereby a pair of pipe sleeves can be fitted together endwise with the pads of one sleeve axially aligned withthe projections of the other sleeve for interlocking engagement between the pad recesses rand the` projections to retain the pair ofsleeves in predetermined connected relation, and whereby the pair of sleevesy can also be fitted together endwise with the pads on one sleeve axially aligned with the spaces between the projections on the other sleeve for more compact nesting of thesleeves.

3. A pipe sleeve comprising a` one-piece tubular member of'deectable plastic material having a pair ofY axially aligned cylindrical sections one of which has a slightly larger diameter than the other, attaching means at the outermost end of said one section, cover means at the outermost end of said other section, and connecting means normally interconnecting the innermost ends of said sections to provide a unitary sleeve, said connecting means being disruptible for disconnecting said sectionsl whereby said other section can be telescoped Within said one section for adjusting the length of the pipe sleeve, and said one section being provided with a plurality of sets of integral circumferentially spaced protuberances extending inwardly from the inner surface of said one section for frictionally engaging the exterior ofV said other section when the latter is telescoped within said one section and thereby retaining the sections in desired telescopic adjustment, the respective sets of protuberances being disposed at a plurality ofaxially spaced locations along the length .of said one section so that said sets of protuberances are adapted to be engaged by the innermost end of said other section during telescoping movement ofthe latter and said other section being locally deflectable inwardly to permit the innermost end thereof to be telescoped forcibly beyond a given set of protuberances, whereby the respective sets of protuberances function as stops for axially positioning said other section in predetermined axial increments but also permitting intermediatey positions of adjustment, and the protuberances in each of said sets being circumferentially offset relative to the protuberances of axially adjacent sets, whereby, when portions of said othery section are locally deflected inwardly by ,one of said sets of protuberances at one axial location, other portions of said other section are bulged outwardly to facilitate engagement thereof by an axially adjacent set of protuberances in circumferentially oifset relation to said one set of protuberances.

4. The article of claim 3 further characterized in that,

said connecting means comprises an outwardly extending annular shoulder at the juncture betwen said sections, said shoulder including an annular web portion adapted to be cut for disconnecting said sections and said shoulder having a circumferential groove for receiving and guiding a cutting tool around said web portion.

References Cited THERON E. CONDON, Primary Examiner.l

G. E. LOWRANCE, Examiner. 

1. A PIPE SLEEVE COMPRISING A ONE-PIECE TUBULAR MEMBER OF DEFLECTABLE PLASTIC MATERIAL HAVING A PAIR OF AXIALLY ALIGNED CYLINDRICAL SECTIONS ONE OF WHICH HAS A SLIGHTLY LARGER DIAMETER THEN THE OTHER, ATTACHING MEANS AT THE OUTERMOST END OF SAID ONE SECTION, CLOSURE MEANS AT THE OUTERMOST END OF SAID OTHER SECTION, SAID SECTIONS HAVING AN EXTERNAL SHOULDER THEREBETWEEN, MEANS DEFINING A PLURALITY OF CIRCUMFERENTIALLY SPACED PADS AT THE INTERIOR OF SAID ONE SECTION ADJACENT SAID OUTERMOST END THEREOF, SAID PADS HAVING RECESSES THEREIN, AND A PLURALITY OF CIRCUMFERENTIALLY SPACED PROJECTIONS AT THE EXTERIOR OF SAID OTHER SECTIONS ADJACENT SAID OUTERMOST END THEREOF, SAID PROJECTIONS BEING COMPLEMENTARY TO SAID RECESSES, WHEREBY A PAIR OF SAID SLEEVES CAN BE FITTED TOGETHER ENDWISE WITH THE PADS OF ONE SLEEVE FRICTIONALLY ENGAGING THE EXTERIOR SURFACE OF THE SMALLER DIAMETER SECTION OF THE OTHER 